Paraffin cleaner for oil wells



7, 1939. c A. STILL ET AL 2,179,475

PAHAFFIN CLEANER FOR OIL WELLS Filed July 8, 1939 llfiSZiZl v i /757211 U NE T rarest cl rics IPARAFFIN CLEANER, FOR OIL WELLS Cuthbert A. Still and Lawrence M. Still, Alta Lorna, Tern; Lawrence M. Still assignor to Aldrich (2. Still, Alta Lorna, Tex.

Application July 8, 1939, Serial No. 283,505

10 Claims. ((31. 166-18) This invention relates to apparatus for use in In the drawing: connection with the drilling of oil wells and per- Figure 1 is a view in elevation of the upper tains'particularly to an improved paraffin cleanportion of the rod or body per se of the present er, the present application constituting a continutool, illustrating the arrangement of the finger ation in part of our prior allowed application, receiving recesses thereabout. v 5 Serial No. 251,806, filed January 19, 1939. Figure 2 is a view of the upper portion of the The primary object of the present invention is implement with parts broken away to show details to provide a novel and improved paraffin cleaner of construction. for oil wells which is so designed that it may be Figure 3 is a sectional View taken transversely inserted without difficulty into the well pipe and of the implement above the fingers and looking 10 passed through the paraffin deposit therein, even longitudinally of the body to show the working though such deposit may be relatively thick, so arrangement of the fingers when in the well that only a small passageway remains at the casing.

center of the pipe and when drawn back, will pre- Figure 4 is a transverse section taken above and sent for engagement with the body of parafiin, a looking toward one of the working fingers. 15 plurality of cleaning or scraping fingers which Figure 5 is a detailed fragmentary view illus= will effectively remove all of the paraihn from trating the manner in which the finger is adapted the surface of the pipe, starting at the lower end to flex under strain.

of the deposit and working upwardly through the Figure 6 is a View illustrating a modified form well pipe, of the working or scraping finger and the mount- 20 Another object of the invention is to provide in ing therefor. 21. paraffin cleaner of the above described char- Figure 7 is a view in perspective of the modified acter, a central body carrying a series of scraper scraping finger per se. fingers which are so designed and arranged upon Referring now more particularly to the drawand about the body that when they are in operaing, the numeral 9 generally designates the body 25 tive position, they will present a fan-like arrangeof the present paraflin cleaner or scraper device, ment around the body which will clean out the which body is in the form of a steel rod or shaft well pipe in one operation of moving the device of suitable diameter which at its lower end is from the lower part of the parafin deposit upprovided with a threaded reduced extension by wardly, if no obstructions on the wall of the pipe means of which the device may be connected with 30 are encountered. a sinker rod if desired.

Still another object of the invention is to pro- At the upper end of the body l a similar revide in a device of the above described character duced extension 3 is formed which is exteriorly cleaning or scraping fingers which are in the form threaded and is adapted for connection with an of flat strips or bands of resilient material which, adapter l which comprises an elongated body of 35 in the event that an obstruction is encountered in the same overall diameter as the rod body i and drawing the device through the well pipe, will flex which has a central bore 5 therethrough which or yield so that the device may come through at its lower end merges with the enlarged in- Without having any of the scraper fingers damteriorly threaded socket 6 in which the extension aged, such fingers after passing the obstruction 3 is threadably se ur The bore 5 is designed returning to their former straight condition by to receive a suspension cable, the lower end of 40 reason of their resiliency. which is secured by the extension 3 against the Other advantages of the invention will become inner end of the socket 6, so that the cleaner apparent as the description of the same proceeds device may be raised and lowered by such cable.

and the invention will be best understood from a In order that the coupling between the adapter 45 consideration of the following detailed descrip- It and the upper end of the body imay be made tion taken in connection with the accompanying secure, there is provided a locking key l which is drawing forming part of this specification, with passed through a slot 8 in the lower end of the the understanding, however, that the invention adapter t for engagement in a socket or recess 9 is not to be confined to any strict conformity in the side wall of the extension 3 and there is 5 with the showing of the drawing but may be then threadably secured to and about the lower changed or modified so long as such changes or end of the adapter, the collar ill which covers the modifications mark no material departure from key l and holds it in place. the salient features of the invention as expressed In carrying out the present invention, the rod in the appended claims. body I is provided with a spirally arranged series 55 of milled slots, each of which indicated by the numeral H, which slots extend in a longitudinal direction on the rod and are slightly ofiset in their spiral arrangement around the rod, as shown.

In and adjacent the lower end of each slot M, a stop body i2 is secured by welding or in any other suitable manner and extending transversely of each slot adjacent the inner side thereof and slightly above the top of the stop body it is a transversely extending pivot pin 53.

Each of the pivot pins i3 passes through an eye Hi which is formed at one end of a scraper finger 15 which swings freely upon the pin i3 and when swung outwardly and downwardly thereof, rests upon the top of the adjacent block I2 so that it will be held outwardly extending from the rod and perpendicular thereto in the manner illustrated. Each of these fingers I5 is in the form of a short fiat strip or ribbon of spring metal and each is designed to lie substantially entirely within its slot ll when it is swung upwardly on its pin it. By this means the rod can be easily inserted into a well even though such well may have a thick deposit of parafiin upon the inner wall of the well pipe so that there is only left a small central passage through which the rod can pass. Since there are no obstructions on the rod and the spring fingers swing upwardly into substantially a flat position at the side of the rod, it will be readily seen that the rod may easily slip downwardly of its own weight past a thick paraffin deposit.

The length of the spring fingers is such that 7 when all of the fingers are in down or operative position with the rod l at the center of the drill pipe, the outer ends of the fingers will come into close proximity with the wall of the pipe. In addition to this, by arranging the spring fingers spirally around the rod and offsetting each one only slightly from the adjacent ones, the'fingers will have an overlapped operating relation such that their outer ends will form or out side by side parallel paths through the paraffin deposit as the device is drawn upwardly through the well and thus if no obstructions are encountered by the fingers in drawing the device through the well, all of the parafiin will be removed from the inner surface of the pipe in the one operation of pulling the device up through the deposit. The arrangement of the spring fingers when all are in operative position and when viewing the same from the top of the cleaner, that is, when looking lengthwise of the rod from the top thereof, is as illustrated in Figure 3, wherein it will be seen that the fingers form a complete collar around the rod which at its outer periphery conforms to the curvature of the well pipe.

In Figures 5 and 6 there is illustrated a slightly modified form of the finger structure i5. In Figure 5 a portion only of the finger carrying body is illustrated, this body being indicated generally by the numeral 16. It will be understood that this body iii is of the same construction as the body I in that it is provided with a plurality of recesses or slots ll corresponding with the slots I! and arranged in the same order in the body it as the slots H are arranged in the body I.

The lower end of each of the slots H is formed to provide an abutment wall It? and just above this wall there extends transversely of each slot ll a pivot pin 59 on which is oscillatably sup' ported the modified scraper finger, which is here indicated generally by the numeral 28. This modified scraper finger is formed of a stifi resilient wire or bar material and has the body portion 21 which terminates at one end in the flattened scraper blade 22. At its opposite end, the body merges with the coil 23 which performs the double function of a spring and a sleeve corresponding with the sleeve M of the finger II. The end of the coil opposite that to which the body 2| is joined terminates in the stop finger 2 1 which is substantially perpendicular to the body 2!. The pivot i9 extends through the coil sleeve 23 and the stop finger 24 bears against the shoulder i8 when the finger is extended outwardly from the body l6, as shown in Figure 5. It will be readily obvious that when the tool is introduced into the well hole, the finger 28 will oscillate upwardly to enter the slot or recess IT in the same manner as the fingers i5 move into their recesses ll, thus permitting the tool to slip down into the well.

In the use of the present tool, the body of the tool will be lowered into the well below the paraffin deposit by means of a cable connected with the adapter at the upper end of the tool body and in being lowered the finger IE5 or 20 will be swung upwardly or closed by contact with the paraifin wall as the tool moves downwardly, thus permitting the tool to move into working position easily and smoothly. After the device has been lowered to the desired position beneath the paraffin deposit or to the desired position i in the paraffin deposit, the teeth will swing outwardly so that their outer ends will engage against the wall of the deposit and when the tool is then drawn upwardly the ends of the teeth will dig into the deposit of paraffin and this will cause them to move into positions where they will be perpendicular to the body to which they are pivotally attached. The fingers I5 will be held in this perpendicular position with respect to the body I by engagement against the stops [2 which lie beneath them and the fingers Zil will be held in perpendicular relation with the body I6 by the engagement of the stop finger 24 against the wall 58, as shown in Figure 5.

Since both forms of fingers are carried upon their supporting bodies in spirally disposed groups, they will present a fan-like arrangement, as illustrated in Figure 3 in connection specifically with the fingers l5, and thus as the tool is drawn upwardly practically the entire inner surface of the well casing will be engaged by the outer ends of the fingers so that the paraffin will be entirely scraped free.

As previously stated, the fingers I5 are of resilient metal so that in the event of any one of them coming into contact with some fixed object in the well the finger will bend down, as shown in Figure 5, and thus permit the tool to be drawn up without breaking the finger.

In the modified form of the invention, the spiral 23 operates as a spring to permit the finger to yield, although the finger itself is formed of resilient material and would have some fiexibility to yield in a somewhat similar manner to the finger !5. It will be understood, however, that the spiral 23 takes the major portion of the strain and returns the finger to a horizontal position after the interfering object has been passed. It is to be understood, however, that the spiral 23 also functions as a supporting sleeve and that, therefore, where the claims call for a sleeve-like portion, the spiral 23, as well as the part M of the finger i5, is to be understood.

The cable used in connection with devices of this kind is tested to carry approximately 900 pounds weight but it is not permitted to suspend from the cable a weight of more than 500 pounds. With other types of devices where no resilient tooth action is had, if the scraping teeth should I encounter an obstruction, the pull or weight upon the cable would, of course, be greatly increased and might result in the breaking of the cable with the loss of the scraping tool and consequently the well would be choked. By providing the resilient scraper fingers and tempering the same so that they will yield or bend under a strain of approximately 500 pounds, it will be seen that if an obstruction is encountered by the fingers and the strain thereon exceeds 500 pounds, the fingers will bend and thus permit the tool to come up through the pipe and avoid breaking the cable. While such action would result in only a partial cleaning of the pipe, it will be readily apparent that the tool can be again lowered and raised until the cleaning operation is completed.

What is claimed is:

l. A parafiin cleaner for oil wells, comprising a rod body, means for attaching a cable to one end of said body, a plurality of fingers pivotally attached to the body in a spiral order thereabout to oscillate longitudinally of the body from positions where they extend toward the said end to normal working positions in which they are perpendicular to the body, means for supporting the fingers in perpendicular relation to the body, said fingers having an inherent resiliency whereby they may flex downwardly from said normal perpendicular position upon the application of a pressure of predetermined force thereto.

2. A parafiin cleaner for oil wells, comprising an elongated body having means at one end for the attachment of a supporting cable thereto, said body being provided with a spirally arranged series of outwardly opening slots, a pivot pin extending transversely of each slot, a spring finger pivotally mounted at one end upon each pin, and means in the slot below the finger forming a stop for the adjacent finger whereby the finger will be normally retained in a position perpendicular to the body, each finger being adapted to swing upwardly on its pivot pin into the slot.

3. A parafiin cleaner for oil wells, comprising an elongated body having means at one end for the attachment of a supporting cable thereto, said body being provided with a spirally arranged series of outwardly opening slots, a pivot pin extending transversely of each slot, 2. spring finger pivotally mounted at one end upon each pin, and means in the lower end of each slot forming a stop for the adjacent finger whereby the finger will be normally retained in a position perpendicular to the body, each finger being adapted to swing upwardly on its pivot pin into the slot, each of said fingers being in the form of a fiat strip of resilient metal which is tempered to flex upon the application to the outer end thereof of a predetermined pressure.

l. A parafiin cleaner for oil wells, comprising a rod having means at one end for the attachment of a suspension cable thereto, a series of fiat finger members arranged in a spiral order around the rod and each pivotally attached to the rod, means adjacent each finger forming a stop whereby the finger will be held in a working position perpendicular to the rod, all of the fingers being adapted to swing in the same direction to a position substantially parallel with the rod, and said fingers being spaced in said spiral order so that they will have a progressive overlapping working relation.

5. A parafiin cleaner for oil wells, comprising a rod member, means at one end for the attachment of suspension means thereto, said rod member being provided with a spirally arranged series of longitudinally extending slots, adjacent slots having their ends in overlapping relation, a pivot pin extending transversely of each slot, a fiat spring finger for each slot having a transverse sleeve at one end through which the pivot pin of the slot passes, stop means in the lower part of each slot below the plane of the pivot pin for supporting the spring finger in outwardly extending position perpendicular to the red, the spring fingers being designed to swing all in the same direction into their respective slots, and said slots being so disposed in the spiral series that the fingers when in perpendicular relation with the rod will be arranged in overlapping working positions to form a substantially complete scraping collar about the rod.

6. In a parafiin scraper for oil wells, including a rod having a spirally arranged series of scraping fingers pivotally attached thereto to extend perpendicularly outwardly with respect to the rod, means for attaching a suspension cable, comprising a reduced threaded extension at one end of the rod, an elongated tubular body having the tubular center enlarged at one end into a socket for the threaded reception of said extension, said tubular body being designed to receive a supporting cable with one end secured in said socket by the threaded extension, and locking means coupling the end of the tubular body with said threaded extension whereby accidental separation of the rod and tubular body are prevented.

l. A paraffin cleaner for oil wells, comprising a rod body, means at one end or" the body for attaching a suspension cable thereto, said body having a plurality of recesses in the wall thereof arranged spirally thereabout, a resilient finger member for each recess having a sleeve-like portion disposed in the recess, a pivot pin extending transversely of each recess through the sleevelike portion of the finger member, each of said finger members being adapted to swing in the recess toward the end of the body carrying said attaching means, means whereby when each or" said fingers is swung in the opposite direction it will be maintained extended from its recess in perpendicular relation to the body, and means whereby each of said fingers may be resiliently moved in opposition to said retaining means in a direction away from the said cable attaching means.

8. A parafiin cleaner for oil Wells, comprising a rod body adapted to be lowered into the well, said body having a plurality of recesses in the wall thereof arranged spirally thereabout, a finger member for each recess having a sleeve-like portion at one end constituting a spirally arranged continuation of the finger, the said sleevelike portion of the finger being disposed in a recess, a pivot pin extending transversely of the recess through the sleeve-like portion of the finger, each of said fingers being adapted to swing in the recess toward the upper end of the body, and means forming a part of the sleeve-like portion for engaging a Wall of the recess to maintain the finger perpendicular with respect to the body when the finger is swung outwardly from the body, said spiral-like sleeve forming a yieldable means for permitting the forcible movement of the finger downwardly beyond the said perpendicular position.

9. A paramn cleaner for oil wells, comprising an elongated body adapted to be lowered into a Well, said body having a plurality of recesses formed therein and arranged spirally thereabout, a pivot pin extending transversely of the lower part of each recess and a scraper finger for each recess comprising a body of resilient metal formed at one end to provide a spiral spring constituting a sleeve through which a pivot pin passes, one end of said spiral spring being extended in a direction substantially perpendicular to the body portion of the finger to form a stop member adapted to bear against a wall of the recess whereby said finger Will be held for a scraping operation substantially perpendicular to the supporting body, the finger being adapted to swing upwardly into the adjacent recess to permit the body to enter the Well.

10. As an article of manufacture, a scraper finger for use in a paraffin cleaner of the character described, comprising an elongated body of resilient metal formed at one end to provide an integral spiral spring sleeve, the longitudinal axis of which extends perpendicular to the finger, said spiral spring sleeve at the end remote from the finger terminating in a short stop finger arranged perpendicular to the first finger, the said first finger having its free end flattened to form a scraping blade.

CUTHBERT A. STILL. LAWRENCE M. STILL. 

